Property and Equipment - Property and Equipment (Detail) - USD ($)	Dec. 31, 2018	Dec. 31, 2017
Property, Plant and Equipment [Line Items]
Property plant and equipment, gross	$ 4,193,688	$ 3,829,959
Less accumulated depreciation	(3,033,922)	(2,692,788)
Property Plant and Equipment Net	1,159,766	1,137,171
Computer Equipment [Member]
Property, Plant and Equipment [Line Items]
Property plant and equipment, gross	44,427	33,584
Furniture and Fixtures [Member]
Property, Plant and Equipment [Line Items]
Property plant and equipment, gross	341,582	301,509
Scientific Equipment [Member]
Property, Plant and Equipment [Line Items]
Property plant and equipment, gross	3,658,209	$ 3,494,866
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property plant and equipment, gross	$ 149,470

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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